Answer 1

You must set the path now. You can follow this to get that done.

https://www.tutorialspoint.com/java/java_environment_setup.htm

Once this is done. You can write Java codes in notepad and then save it with .java extension.

To execute on windows platform you can go to command prompt and move to the folder which contains the file.

javac filename.java
// This will compile your code

java filename
// This will execute your code

Answer 2

You can use intelIJ for java codes on pc.